Help: Certain menus have graphical issues and are unreadable

Brave Browser, if installed in the default way - may be installed as a Snap or Flatpak. Snap and Flatpak packages both isolate the app from the system (which can be bad as you see in this thread) preventing access to critical system files needed to function properly.
Can you please check how Brave Browser is installed?

snap list

Flatpak list